G34A tRNAPhe is not a substrate for A-to-I editing enzymes. After incubation with total cell extracts or A-to-I editing enzymes, tRNAs were digested with RNase P1 and separated on cellulose TLC plates. Lanes are as follows: 1, G34A hmt-tRNAPhe without the addition of enzymes; 2, G34A hmt-tRNAPhe with total Hek 293T cell extracts; 3, G34A hmt-tRNAPhe with purified T. brucei ADAT2/ADAT3; 4, T. brucei cytosolic tRNAVal without the addition of enzymes; 5, T. brucei cytosolic tRNAVal with total Hek 293T cell extracts; 6, T. brucei cytosolic tRNAVal with purified T. brucei ADAT2/ADAT3.